Process for the manufacture of sheets of decorated plastic material



J. A. RENOUPREZ PROCESS FOR THE MANUFACTURE OF SHEETS OF DECORATED PLASTIC MATERIAL Filed July 24, 1929 I June 6, 1933.

Patented .lune 6, 1933 UhlTED STATES PATENT OFFC JULES ALBERT RENOUPREZ, OF ROUSSILLON, FRANCE, ASSIGNOR TO E. I. DU PONT DE NEIYIOURS a COIPANY, OF XLMNGTON, DELAWARE EROCESS FOR THE MANUFACTURE OF SHEETS OF DECGRATED PLASTIC MATERIAL Application filed July 24, 1929, Serial No. 380,776, and in. France July 25, 1928.

The present invention concerns a process of manufacture of sheets of decorated plastic material. This process is applicable to all the plastic materials capable ot being 5 worked under a press, tor example to plastic materials the basis ot which is cellulose acetate, nitro-cellulose or other cellulosic derivatives. The raw materials used are sticks and, if desired, sheets of plastic materials; the sticks may be of circular or any other section; the. sticks and the sheets may be coloured, transparent or opaque. The desired decorative eiiects are obtained, in accordance with the invention, by combining sticks and it desired, sheets, of ditl'erent nature in respect ot their colour and particularly their section.

According to the present invention, I provide a process of manufacture ot sheets of decorated plastic material, which consists in arranging sticks ot diterent kinds in a parallel manner, in rows, in interposing, if desired, sheets between the rows ot sticks. and in welding the whole together by pressure in such a manner as to obtain a block,

in cutting this block in parallelopipedon shaped pieces by means of equidistant cuts made in a direction perpendicular to that of the sticks and, it desired, by sections made sa in a direction parallel to that of the sticks,

in assembling by pressure these parallelopipedon shaped pieces, with the faces, which are parallel -to the direction of the sticks, put together, so as to obtain a block then cutting` this block perpendicularly to the direction of the sticks.

The invention may be carried out as tollows:

The sticks of various kinds are placed t parallel to each other in rows, with sheets of plastic material interposed, it desired, between the rows oi sticks, and the whole is welded by pressure so as to obtain a block. This block is then cut into strips by equidistant cuts made in a direction perpendicular to the direction of the sticks, and, if desired these strips are divided by cuts made in a direction parallel to the direction of the sticks. In this manner parallelopipedon shaped pieces are obtained, the two faces of which, perpendicular to the direction Ot the sticks, show a decoration which is governed by the arrangement of the sticks and of the sheets (if any), before being pressed together. These pieces are then put edgewise with their vfaces parallel to the direction of the sticks in contact, and assembled together by pressure. By operating in this manner, the faces of the parallelopipedon shaped pieces perpendicular to the direction of the sticks are brought in two parallel planes constituting the 'faces of the block so obtained. This block is linally cut perpendicularly to the direction of the sticks and in this manner sheets which are decorated throughout their mass are obtained.

Here are, as example, two methods of carrying out the process.

Example 1 Sticks of plastic material with a basis of cellulose acetate are disposed quincuncially between sheets of plastic. material the basis of which is cellulose acetate, as shown on Figure 1. These sticks and these sheets still contain a sutlicient percentage of solvent to allow them to be shaped. The whole is put into a press; in this manner a block is obtained diagrammatically represented in Figure 2. This block is cut in a direction perpendicular to the direction of the sticks into parallelopipedon shaped strips, a few centmetros in width, numbered 1, 2, 3, 4, on Figure 2. These strips are placed edgewise by turning the strip No. 1 through 90 about its axis A1, the strip N o. 2 through 90 through its aXis A2 etc., and the whole is placed into a press so as to obtain a new block. The strips may be turned in the same direction or first in one direction and then in the other, alternately. In the iirst case the block represented diagrammatically on Figure 3 is obtained by pressing, in the second case the block shown diagrammatically on Figure 4; is obtained. These blocks are atterwards cut in sheets perpendicularly to the direction of the sticks. These sheets exhibit'- a pattern which, in the case of the block shown on Figure 4, has a certain symmetrical character. It will be understood that, by modifying the mode of assembling the strips put edgewise it is possible to obtain varied decoration effects.

Eaample 2.-One proceeds as in Example l, up to the obtainment of the strips. These strips are then cut into parallelopipedon shaped pieces of equal size by cuts made in a direction parallel to that of the sticks, as indieated on Figure 5, where these pieces are numbered 11, l2, etc., 21, 22, etc. These pieces are placed edgewise as follows: the pieces 11, 13, l5 are turned through 90 in one direction about the axis A1, the pieces 22, 2*, 2G are turned through 90o in the same direction about the axis A2 etc.; the pieces 12, 14, 16 are turned in the opposite direction through 90o about the axis A1, the pieces 21, 23, 25 are turned through 90 about the axis A2 etc. The whole is put into a press, and the block obtained, shown diagrammatically in Figure 6, is cut in sheets erpendicularly to the direction of the sticks.

hese sheets have a pronounced symmetrical character.

r It will be understood that by putting the pieces edgewise together in a different man` ner, varied decorative effects can be obtained. It is also possible to cut the pieces 11, l2 21, 22 so that they have unequal lengths, which allows other effects to be obtained.

These two examples put in evidence the principal advantages which the new process offers, namely, the facility of execution and the possibility of obtaining decorative effects which are extremely varied, since the decoration of the sheets obtained depends from a large number of factors which can be varied independently.

Vhat I claim and desire to secure by Letters Patent is 1. A process for the manufacture of decorated sheets which comprises arranging in parallel rows a plurality of variously colored and shaped sticks of a plastic material containing a cellulose derivative as its base and a sufficient amount of solvent to permit shaping, subjecting said mass to pressure, cutting the resultant block equidistantly in a direction perpendicular to the sticks to produce parallelopipedon shaped pieces, arranging said parallelopipedon shaped pieces with the faces together which are parallel to the sticks, subjecting said mass to pressure, and cutting the block perpendicular to the direction of the sticks.

2. A process for the manufacture of decorated sheets which comprises arranging in parallel rows a plurality of variously colored and shaped sticks of a plastic material containing a cellulose derivative as its base and a suficient amount of solvent to permit shaping, interposing between said rows sheets of a plastic material similar to said sticks, subjecting said mass to pressure, cutting the re-v sultant block equidistantly in a direction perpendicular to the sticks to produce parallelopipedon shaped pieces arranging said parallelopipedon pieces with the faces together which are parallel to the sticks, subjecting said mass to pressure, and cutting the block perpendicular to the sticks.

ln testimony whereof I have signed my name to this specification.

JULES ALBERT RENOUPREZ. 

